Genesis 25:27

“And the boys grew, etc.] In stature, became strong and fit for business, and betook themselves to different employments: and Esau was a cunning hunter, a man of the field: whose business lay in tilling and sowing it, which his father Isaac followed sometimes; or rather he chose to range about the field and hunt after beasts and birds, in which he was very expert, and contrived traps and snares to catch them in; and this course of life was most agreeable to his temper and disposition, being active, fierce, and cruel; according to the Targum of Jonathan, he was also a hunter and slayer of men, Nimrod and Henoch his son: and Jacob was a plain man; an honest plain hearted man, whose heart and…”

“the boys grew--from the first, opposite to each other in character, manners, and habits.”

“25:27-34 Jacob and Esau each developed in accord with his initial characteristics (25:24-26). Esau, the reddish, hairy man, cared about physical things rather than spiritual things (see Heb 12:16); he was finally overcome by physical appetites and sold his birthright. Jacob, the heel grabber, knew the birthright’s value and drove a ruthless bargain to gain it presumptuously from his brother. 25:27 Esau was a skillful hunter and an outdoorsman—a wild man who loved wild country. Jacob had a quiet (or even) temperament and preferred to stay at home (literally dwelling in tents)—i.e., he was civilized.”